One-Pot Synthesis of SnO 2 -rGO Nanocomposite for Enhanced Photocatalytic and Anticancer Activity.

Metal oxide and graphene derivative-based nanocomposites (NCs) are attractive to the fields of environmental remediation, optics, and cancer therapy owing to their remarkable physicochemical characteristics. There is limited information on the environmental and biomedical applications of tin oxide-reduced graphene oxide nanocomposites (SnO 2 -rGO NCs). The goal of this work was to explore the photocatalytic activity and anticancer efficacy of SnO 2 -rGO NCs. Pure SnO 2 NPs and SnO 2 -rGO NCs were prepared using the one-pot hydrothermal method. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), UV-Vis spectrometry, photoluminescence (PL), and Raman scattering microscopy were applied to characterize the synthesized samples. The crystallite size of the SnO 2 NPs slightly increased after rGO doping. TEM and SEM images show that the SnO 2 NPs were tightly anchored onto the rGO sheets. The XPS and EDX data confirmed the chemical state and elemental composition of the SnO 2 -rGO NCs. Optical data suggest that the bandgap energy of the SnO 2 -rGO NCs was slightly lower than for the pure SnO 2 NPs. In comparison to pure SnO 2 NPs, the intensity of the PL spectra of the SnO 2 -rGO NCs was lower, indicating the decrement of the recombination rate of the surfaces charges (e - /h + ) after rGO doping. Hence, the degradation efficiency of methylene blue (MB) dye by SnO 2 -rGO NCs (93%) was almost 2-fold higher than for pure SnO 2 NPs (54%). The anticancer efficacy of SnO 2 -rGO NCs was also almost 1.5-fold higher against human liver cancer (HepG2) and human lung cancer (A549) cells compared to the SnO 2 NPs. This study suggests a unique method to improve the photocatalytic activity and anticancer efficacy of SnO 2 NPs by fusion with graphene derivatives.